Carburettor device

ABSTRACT

The present invention relates to apparatus for improving the mixing between fuel oil and air by insertion in the inlet manifold of an engine such as an internal combustion engine and comprises a reservoir having a plurality of venturi tubes communicating therewith transversely of the mixture stream within the manifold whereby liquid fuel entering the reservoir is at least partially vapourized by the influence of the mixture stream passing over the ends of the venturi tubes.

United States Patent 91 Dyson CARBURETTOR DEVICE [75] Inventor: Eugene Dyson, Warwickshire,

England 731 Assignees Home Tune Limited, Le'atherhead,

Surray, Great Britain [22] Filed: Aug. 2, 1972 [21] Appl. No.: 277,269

[52] US. Cl. 261/78 R, 48/180 R, 261/DIG. 55

[51] Int. Cl. F02m 29/04 [58] Field of Search 261/78 R, DIG. 55; 48/180 R [56] References Cited UNITED STATES PATENTS 2,104,315 l/l938 Abramson 261/78 R 2,589,946 3/1952 Linn 2,889,214 6/1959 Linn 48/180 R [4 1 Apr. 23, 1974 2,986,378 5/1961 Moseley 261/78 R X 3,393,984 7/1968 Wisman 261/78 R X 3,467,072 9/1969 Toesca 26l/D1G. 55

Primary Examiner-Tim R. Miles Assistant Examiner-Richard L. Chiesa Attorney, Agent, or Firm-Stepnb, Schwaab and Linn 57 ABSTRACT The present invention relates to apparatus for improving the mixing between fuel oil and air by insertion in the inlet manifold of an engine such as an internal combustion engine and comprises a reservoir having a plurality of venturi tubes communicating therewith transversely of the mixture stream within the manifold whereby liquid fuel entering the reservoir is at least partially vapourized by the influence of the mixture stream passing over the ends of the venturi tubes.

8 Claims, 4 Drawing Figures (-ATEHTEU APR 23 m4 SHEET 2 OF 2 FIG. 4.

CARBURETTOR DEVICE The present invention relates to carburetion devices and has particular reference to a device for insertion in the inlet manifold of an engine downstream of a carburettor to provide improved mixing between the fuel and the air passing through the manifold to the engine.

The majority of engines are carburated by means of a carburettor fixed to an inlet manifold. This carburettor serves to provide a spray of fuel such as petrol into a stream of air passing therethrough to provide a distribution of petrol vapour within the air. The amount of air passing through a choke tube of the carburettor and into the inlet manifold is usually controlled by means of a butterfly-type valve which comprises a plate pivoted with respect to the choke tube across a diameter and movable between a position in which it substantially obturates the choke tube and the position in which it is substantially disposed in a plane containing the longitudinal axis of said choke tube thereby providing the minimum resistance to air flow through the choke tube itself.

A principal disadvantage of this arrangement is that with the throttle control valve flap in only a partially open position, the lower most or trailing edge of the butterfly acts upon the vapour laden airstream to produce aerofoil condensation and neat petrol tends to collect on the trailing edge of the butterfly valve and is dragged off as globules or distinct drops into the mixture stream and is passed in the undispersed state into the combustion chamber of the engine as neat fuel.

During combustion, this fuel is incompletely burnt with a resultant dirty exhaust and inefficiency of the engine.

According to the present invention there is provided apparatus for improving the mixing between fuel and air in the inlet manifold of an engine which apparatus comprises a reservoir adapted to be disposed in said manifold juxtaposed with an edge of a partially open butterfly or like valve, said reservoir having an open end disposed towards said valve, a plurality of venturi tubes each communicating with said reservoir and extending transversely of the mixture stream within said manifold and at least one secondary tube disposed with a component counter-current said gas stream whereby liquid fuel entering said reservoir is at least partially vapourized by the influence of said mixture stream passing over the ends of said venturi tubes.

The apparatus in accordance with the present invention is, therefore, preferably juxtaposed beneath the trailing edge of the partially open butterfly valve whereby drops of liquid fuel pass from the end thereof into the reservoir. The air flow over the venturi tubes is thought to create an additional depression within the reservoir itself thereby aiding further vapourization of the fuel within the reservoir and passage of the airstream passed the secondary tube results in a bleed stream of fuel/air mixture which additionally assists vapourization of the fuel within the reservoir whereby a more even distribution of fuel within the mixture stream passing along the inlet manifold is obtained.

The reservoir is preferably longitudinal and may have a funnel shaped opening at its open end towards the butterfly valve. The secondary tube may be disposed at the closed end of the reservoir at an angle towards the open end thereof. The reservoir may be formed of a longitudinal body member and may be constituted by a cylindrical bore therein, the venturi tubes being disposed in a side wall thereof.

The body member may have, towards its open end, an adjustable stud for securing the apparatus in the inlet manifold of the engine. The adjustable stud may comprise a fixed threaded stud and a threaded sleeve therefor, an end of which is adapted to bear against a wall of the manifold within which the apparatus is to be disposed.

The venturi are preferably each substantiallyperpendicular to the longitudinal axis of the reservoir and the venturi tubes arealso preferably arranged in rows of at least two per row, each row being disposed in a plane containing the longitudinal axis of the reservoir. The number of venturi tubes may be double the number of secondary tubes.

The invention also includes carburation assemblies for internal combustion engines incorporating the apparatus of the invention and further includes internal combustion and diesel engines incorporating the apparatus of the invention.

Following is a description by way of example only and with reference to the accompanying drawings of apparatus in accordance with the present invention.

In the drawings:

FIG. 1 is a perspective view of an apparatus in accordance with the present invention; FIG. 2 is a side view of the apparatus of FIG. 1;

FIG. 3 is a section through a manifold looking down upon the apparatus of the present invention disposed therein and showing the means of attachment;

FIG. 4 is a section of the lines VI VI of FIG. 3 additionally showing the butterfly valve with the carburettor assembly disposed thereabove. de

The apparatus in accordance with the present invention comprises a reservoir 10 formed of a longitudinal sleeve open at its first end 11 and having a central cylindrical longitudinally extending bore 12 therein. The bore 12 is closed at the second end 13 of the reservoir 10. The walls 14 defining the opening 1 1 in the first end of the reservoir body 10 have a frusto conical form defining a funnel shaped entrance. The external surface of the body 10 is generally hexagonal in form and the body 10 is, in this embodiment, formed of brass.

The body 10 has, towards its upper end, three circumferentially spaced, radially directed bores 17 each of which are threaded. A first bore 17' has a radially extending stud 18 threaded thereinto, the stud 18 being secured by means of an adhesive such as that available commercially under the trade mark Araldite. The stud 18 carries an internally threaded sleeve 19 having a pointed outer end 20, the arrangement being such that rotation of sleeve 19 with respect to stud l8 varies the spacing of pointed end 20 from the longitudinal axis of reservoir 12; the sleeve 19 being adjusted to secure the apparatus in its operative location (see FIG. 3).

Each of the remaining bores 17 carries a support member 22 adapted to engage with an internal surface 50 of an inlet manifold in which the apparatus is to be located.

The body 10 carries three rows of venturi tubes 25 each row being constituted by two tubes. Each row is disposed in a face 26 of the hexagonal outer surface of body 10 and is adjacent at least one other row of venturi tubes 25.

Each venturi tube 25 comprises a cylindrical tube 26 having a cylindrical bore 28 and a flared frusto conical opening 27 at the outer end. Each tube 26 is reduced at its inner end 29 and is a tight fit within a corresponding bore 30 in body whereby the tube 26 is rigidly retained therein.

Towards the end 13 of each of faces 26 carrying a row of the venturi tubes 25 there is provided a secondary tube 31 which is longer in radial extent than each of tubes 25. Each tube 31 has a central cylindrical bore 32 having a frusto-conical opening 33 at the outer end thereof. The tube 31 is reduced at its inner end and is adapted to be accommodated in the bore 34 in the side wall of body 10 towards the end 13 thereof, the bore being angled to define an acute angle between the axis of the bore and the longitudinal axis of body 10 towards the open end thereof with the result that tube 31 is disposed convergently with the tube 25 adjacent thereto.

The apparatus is disposed in inlet manifold 49 in the manner described above and is disposed towards the carburettor assembly 51 secured thereto so that when the butterfly valve 52 is disposed in the partly opened position, the trailing edge 53 is juxtaposed the open end 11 of body 10 the arrangement being such that the butterfly 52 is free to move to its fully open position.

In operation, the fuel flowing downwardly through the choke tube 51 as shown in FIG. 4 produces aerofoil condensation from the trailing edge 53 of the partially open butterfly valve 52. The condensation detaches from edge 53 and enters the funnel shaped open end 1 l of the reservoir to collect towards the bottom of the reservoir end 13. The effect of the airstream over the end of the venturi tubes 25 is to produce a depression of the inner end of the tubes, thereby producing turbulent flow and an increase in velocity of airflow in reservoir 12. This increased velocity of airflow produces additional vapourization of fuel collected within the reservoir and results in an improved distribution and improved vapourization of the fuel after passing the device.

Tests have shown that cars fitted with the device in 4 accordance with the invention show cleaner exhausts and greater economy and improved efficiency.

I claim:

1. Apparatus for improving the mixing between fuel and air in the inlet manifold of an engine which apparatus comprises a reservoir adapted in its operative location to be disposed in said manifold juxtaposed with an edge of a partially open butterfly or like valve, said reservoir having an open end disposed towards said valve, a plurality of venturi tubes communicating with said reservoir and adapted to extend transversely of the mixture stream within said manifold and including at least one secondary tube disposed with a component counter-current said gas stream whereby liquid fuel entering said reservoir is at least partially vapourized by the influence of said mixture stream passing over the ends of said venturi tubes.

2. Apparatus according to claim 1 wherein the reservoir is longitudinal and has a funnel shaped opening at its open end.

3. Apparatus as claimed in claim 1 wherein the secondary tube is disposed at the closed end of the reservoir and is angled towards the open end thereof.

4. Apparatus as claimed in claim 1 wherein the reservoir comprises a longitudinal body member having a cylindrical bore therein, the venturi tubes being disposed in a side wall thereof.

5. Apparatus as claimed in claim 4 wherein the body member has, towards its open end, an adjustable stud for securing the apparatus in the inlet manifold of an internal combustion engine. 1

6. Apparatus as claimed in claim 1 wherein the venturi tubes are each substantially perpendicular to the longitudinal axis of the reservoir.

7. Apparatus as claimed in claim 1 wherein the venturi tubes are in rows of at least two per row, each row being disposed in a plane containing the longitudinal axis of the reservoir. v

8. Apparatus as claimed in claim 1 wherein the number of venturi tubes is double the number of secondary tubes. 

1. Apparatus for improving the mixing between fuel and air in the inlet manifold of an engine which apparatus comprises a reservoir adapted in its operative location to be disposed in said manifold juxtaposed with an edge of a partially open butterfly or like valve, said reservoir having an open end disposed towards said valve, a plurality of venturi tubes communicating with said reservoir and adapted to extend transversely of the mixture stream within said manifold and including at least one secondary tube disposed with a component counter-current said gas stream whereby liquid fuel entering said reservoir is at least partially vapourized by the influence of said mixture stream passing over the ends of said venturi tubes.
 2. Apparatus according to claim 1 wherein the reservoir is longitudinal and has a funnel shaped opening at its open end.
 3. Apparatus as claimed in claim 1 wherein the secondary tube is disposed at the closed end of the reservoir and is angled towards the open end thereof.
 4. Apparatus as claimed in claim 1 wherein the reservoir comprises a longitudinal body member having a cylindrical bore therein, the venturi tubes being disposed in a side wall thereof.
 5. Apparatus as claimed in claim 4 wherein the body member has, towards its open end, an adjustable stud for securing the apparatus in the inlet manifold of an internal combustion engine.
 6. Apparatus as claimed in claim 1 wherein the venturi tubes are each substantially perpendicular to the longitudinal axis of the reservoir.
 7. Apparatus as claimed in claim 1 wherein the venturi tubes are in rows of at least two per row, each row being disposed in a plane containing the longitudinal axis of the reservoir.
 8. Apparatus as claimed in claim 1 wherein the number of venturi tubes is double the number of secondary tubes. 